Cloud seeding: Making rain in desert by a naturalised process

Cloud seeding operations are being carried out with the government’s support, all in order to enhance precipitation

An aerial shot of Abu Dhabi as the aircraft ascends for cloud seeding. — Supplied photo 

It’s tempting to call them rainmakers, the people who whoosh up into the skies, inject salts into fluffy clouds and fly back down to the ground. Except they’re not rainmakers.

The pilot who makes clouds rain in UAE Nivriti Butalia Michael anstis, NCMS Cloudseed Pilot, has lived in the UAE for nearly eight years. He flies 300 hours a year. And he’s been cloud seeding for 5 years. Anstis has a flair for merging simple with technical, switching easily from “predominant wind flow” and “vertical columns of downward moving air” to “Every cloud is different. Every cloud grows differently. It’s almost like an art.” Excepts from an interview Did you always want to be a pilot? How did cloud seeding happen to you? I grew up on a farm in New Zealand, after finishing high school, I’d thought of three career paths, an engineer, a farmer or a pilot. Tell us about cloud seeding. It’s always amazing to see a cumulonimbus cloud reach maturity over the dry desert. When the rain starts to fall from it, the weight of the falling water pulls down massive amounts of air. This rain simply hits the surface, but the air has nowhere to go except flow outwards, sideways in all directions. It picks up the dust from the desert and creates this huge inverted mushroom cloud of dust that can only be seen from above. In the centre it’s nice and clear, but it has a rapidly growing wet spot from the shaft of the falling rain. What’s the biggest thrill about your job? After so many hours of flight time, do you still have a sense of wonder about being in the clouds? Flying is a thrill all by itself, but flying in rough weather is challenging and quite mentally demanding. Flying over the high terrain to the East, whilst maneuvering in, below and around the weather and turbulence on the instruments, communicating with Air Traffic Control as well as the meteorologists over the radios, and all the while, cross checking aircraft systems and maintaining a safe flight profile requires a keen level of situational awareness. I enjoy this challenge. What’s the downside of the job? Yes, the job comes with an unpredictable schedule, but it also is a high risk job. The level of discipline has to be high to mitigate the level of risk for the safety of each flight. If this discipline slips or is pushed, it can be frustrating. You mentioned thunderstorms in Florida. What was that like? I lived in Florida for seven years flight instructing, Florida has summertime thunderstorms most afternoons. Having the exposure of flying around these weather systems made it easier to pickup cloud seeding skills. Are all fluffy clouds are rough and bumpy? Yes, fluffy clouds are cumuliform clouds, they have cumulus in their names, the flat sheet type clouds are stratiform clouds that are thin and smooth to fly through. How do your friends and family react to your job?  Local UAE friends often call me about the weather if it rains over a town or city they’re in. When I land from one of these days, there’s often half a dozen missed calls and messages when I turn my phone back on. If there is a weather system coming, I’ll often message friends who I know might have their clothes drying outside. Are there two pilots per aircraft per operation or just the one? During daylight hours we have single pilot and at night we have two pilots. Were you a commercial pilot earlier/ did you want to be? No, I haven’t flown commercially, in the sense of flying for an airline. I would need to repeatedly tell myself to fly away from the bad weather, not towards it, if I ever did. Can you eat in the plane? All that work must make you hungry. (laughs) No, I just drink water. With your adrenaline pumping, it’s difficult to eat. nivriti@khaleejtimes.com

In 2014, there were 193 flights that carried out ‘rain enhancing operations’. And so far in 2015, there have been 20 flights — all out of the Abu Dhabi-Al Ain region.

Cloud seeding in the UAE began in the 1990s. Back then these operations were done at random and it was only in 2001 when some scientific studies began on the subject.

The National Centre for Metrology and Seismology (NCMS) in 2004 started implementing solo projects, as NCMS puts it, “with our own facilities”.

Cost of these operations? They won’t say. But if there’s one thing Ali Al Musallam, Head of the Cloud Seeding Operations Section at NCMS, does empahsise, it is this: “We do not cause rain, we simply enhance it.”

One of the six cloudseed pilots for the six aircrafts deployed for this purpose, Mike — Michael Anstis — says, of the most repetitive, frequent questions people ask is: “Do you really make it rain”?

No. Nobody makes it rain. They do though make it rain (more). Cloud seeding or rain enhancement is one kind of weather modification. (There other kinds: fog dispersal, decrease of lightning, hail suspension)

The other misconceptions that annoy Musallam are layman conspiracy theories. Cloud seeding has nothing to do with climate change, he says. “And no, dust storms are not caused when cloud seeding happens — those are simply variables in the weather”.

 Raindrops keep falling

One cloud contains up to 270 million gallons of water — without being seeded. When they are seeded successfully, there is a 30 per cent increase in rain — whenever it does rain. And that rain then creates water worth $300,000.  

That 30 per cent extra is when the air is free of pollutants, that is a ‘non-turbid atmosphere’. Haze is no good. Because when the air is turbid and polluted, there is a 10-15 per cent chance of success. There’s much cost-effectiveness to think about.

This keenness to increase rain, given the desert realities, cannot be underestimated. In early 2015, a $5 million dollar programme was launched by the Ministry of Presidential Affairs (MoPA) mainly to expand global water security. They’re looking for ways to “enhancing precipitation to increase rainfall in the UAE, as well as other arid and semi-arid areas in the region”.

 How it’s done?

Cloud seeding is done when a cocktail of potassium chloride and sodium chloride is injected in cumulus clouds. Once these are injected with salts, they further fluff up, become heavy and cause some bonus droplets. The principle is the same as when salt spills on your kitchen counter, and overnight it turns into beads of moisture.

According to Sufian Farrah, a senior forecaster at NCMS: “The success rate of cloud seeding, when done in turbid atmosphere, that is when there are pollutants in the air, is a mere 10-15 per cent. In non-turbid conditions, there is up to a 30 per cent increase in rain if clouds are successfully seeded”.

Mike poses with his cloud seeding aircraft  

The ingredients of the flare

Potassium chloride and sodium chloride are best to attract moisture. Sometimes up to 7 per cent magnesium is added to the two aforementioned components to enable firing. “Magnesium, though, is not always added as then the composition changes and the molecules turn smaller in size,” says Farrah.

 Rough days at work for pilots

One danger of cloud seeding operations is that the pilots are sent up when the weather is rough, when the clouds are fat and bumpy. The turbulent conditions a commercial pilot would avoid are the very ones that a cloudseeding pilot embraces. Or as pilot Mike says: “We have to fly into the dangerous parts of the sky.”

nivriti@khaleejtimes.com